Adding upstream version 2.39.3.upstream/2.39.3

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 175 insertions, 0 deletions

diff --git a/libmount/src/hook_owner.c b/libmount/src/hook_owner.c
new file mode 100644
index 0000000..11b238c
--- /dev/null
+++ b/libmount/src/hook_owner.c
@@ -0,0 +1,175 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * This file is part of libmount from util-linux project.
+ *
+ * Copyright (C) 2022 Karel Zak <kzak@redhat.com>
+ *
+ * libmount is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation; either version 2.1 of the License, or
+ * (at your option) any later version.
+ *
+ *
+ * This is X-mount.owner=, X-mount.group= and X-mount.mode= implementation.
+ *
+ * Please, see the comment in libmount/src/hooks.c to understand how hooks work.
+ */
+#include <sched.h>
+
+#include "mountP.h"
+#include "fileutils.h"
+
+struct hook_data {
+	uid_t owner;
+	gid_t group;
+	mode_t mode;
+};
+
+/* de-initiallize this module */
+static int hookset_deinit(struct libmnt_context *cxt, const struct libmnt_hookset *hs)
+{
+	void *data;
+
+	DBG(HOOK, ul_debugobj(hs, "deinit '%s'", hs->name));
+
+	/* remove all our hooks and free hook data */
+	while (mnt_context_remove_hook(cxt, hs, 0, &data) == 0) {
+		free(data);
+		data = NULL;
+	}
+
+	return 0;
+}
+
+static int hook_post(
+			struct libmnt_context *cxt,
+			const struct libmnt_hookset *hs __attribute__((__unused__)),
+			void *data)
+{
+	struct hook_data *hd = (struct hook_data *) data;
+	const char *target;
+	int rc = 0;
+
+	assert(cxt);
+
+	if (!hd || !cxt->fs)
+		return 0;
+
+	target = mnt_fs_get_target(cxt->fs);
+	if (!target)
+		return 0;
+
+	if (hd->owner != (uid_t) -1 || hd->group != (uid_t) -1) {
+		DBG(CXT, ul_debugobj(cxt, " lchown(%s, %u, %u)", target, hd->owner, hd->group));
+		if (lchown(target, hd->owner, hd->group) == -1)
+			return -MNT_ERR_CHOWN;
+	}
+
+	if (hd->mode != (mode_t) -1) {
+		DBG(CXT, ul_debugobj(cxt, " chmod(%s, %04o)", target, hd->mode));
+		if (chmod(target, hd->mode) == -1)
+			return -MNT_ERR_CHMOD;
+	}
+
+	return rc;
+}
+
+static inline struct hook_data *new_hook_data(void)
+{
+	struct hook_data *hd = calloc(1, sizeof(*hd));
+
+	if (!hd)
+		return NULL;
+
+	hd->owner = (uid_t) -1;
+	hd->group = (gid_t) -1;
+	hd->mode = (mode_t) -1;
+	return hd;
+}
+
+static int hook_prepare_options(
+			struct libmnt_context *cxt,
+			const struct libmnt_hookset *hs,
+			void *data __attribute__((__unused__)))
+{
+	struct hook_data *hd = NULL;
+	struct libmnt_optlist *ol;
+	struct libmnt_opt *opt;
+	int rc = 0;
+
+	assert(cxt);
+	assert(cxt->map_userspace);
+
+	ol = mnt_context_get_optlist(cxt);
+	if (!ol)
+		return -ENOMEM;
+
+	opt = mnt_optlist_get_named(ol, "X-mount.owner", cxt->map_userspace);
+	if (opt) {
+		const char *value = mnt_opt_get_value(opt);
+		if (!value)
+			goto fail;
+		if (!hd) {
+			hd = new_hook_data();
+			if (!hd)
+				goto fail;
+		}
+		if (mnt_parse_uid(value, strlen(value), &hd->owner))
+			goto fail;
+	}
+
+	opt = mnt_optlist_get_named(ol, "X-mount.group", cxt->map_userspace);
+	if (opt) {
+		const char *value = mnt_opt_get_value(opt);
+		if (!value)
+			goto fail;
+		if (!hd) {
+			hd = new_hook_data();
+			if (!hd)
+				goto fail;
+		}
+		if (mnt_parse_gid(value, strlen(value), &hd->group))
+			goto fail;
+	}
+
+	opt = mnt_optlist_get_named(ol, "X-mount.mode", cxt->map_userspace);
+	if (opt) {
+		const char *value = mnt_opt_get_value(opt);
+		if (!value)
+			goto fail;
+		if (!hd) {
+			hd = new_hook_data();
+			if (!hd)
+				goto fail;
+		}
+		if (mnt_parse_mode(value, strlen(value), &hd->mode))
+			goto fail;
+	}
+
+	if (hd) {
+		DBG(CXT, ul_debugobj(cxt, " wanted ownership %d:%d, mode %04o",
+					hd->owner, hd->group, hd->mode));
+		rc = mnt_context_append_hook(cxt, hs,
+				MNT_STAGE_POST,
+				hd, hook_post);
+		if (rc < 0)
+			goto fail;
+	}
+	return 0;
+fail:
+	if (rc == 0)
+		rc = -MNT_ERR_MOUNTOPT;
+	free(hd);
+	return rc;
+}
+
+
+const struct libmnt_hookset hookset_owner =
+{
+	.name = "__owner",
+
+	.firststage = MNT_STAGE_PREP_OPTIONS,
+	.firstcall = hook_prepare_options,
+
+	.deinit = hookset_deinit
+};